[gn build] Port 1874dee

Author: llvmgnsyncbot

llvm/utils/gn/secondary/llvm/lib/BinaryFormat/BUILD.gn

@@ -1,9 +1,12 @@
 static_library("BinaryFormat") {
   output_name = "LLVMBinaryFormat"
-  deps = [ "//llvm/lib/Support" ]
+  deps = [
+    "//llvm/lib/Support",
+  ]
   sources = [
     "AMDGPUMetadataVerifier.cpp",
     "Dwarf.cpp",
+    "MachO.cpp",
     "Magic.cpp",
     "Minidump.cpp",
     "MsgPackDocument.cpp",